feat: add external service detail in subscription management detail overlay

[shahmargi12]

Description

• Added new content to subscription detail overlay on /appsubscription and /servicesubscription pages.

• Endpoint and Response Details:
  • Endpoint: GET /api/apps/{appId}/subscription/{subscriptionId}/provider
  • New Response body content:

 "externalService": {
        "trusted_issuer": "string",
        "participant_id": "string",
        "iatp_id": "string",
        "did_resolver": "string",
        "decentralIdentityManagementAuthUrl": "string",
        "decentralIdentityManagementServiceUrl": "string"
      }
    }

• If any field is missing, it will show as "-".
• Included English and German translations for these fields

Why

This change will provide users with more detailed information about their subscriptions.

Issue

940

Checklist

• I have followed the contributing guidelines
• I have performed a self-review of my own code
• I have successfully tested my changes locally

[sonarcloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud